Motion-picture camera



Dec. 4, 1928.

L. K. BRAREN GEAR TRANSHISSION Filed HOV. 30. 19,25

7219515 1a 17 15,19 21 f a m i 1. Q s @la 45 o-\v s Zorn KonraaZmcren Dec. 4, 1928. 1,694,031

L. K. BRAREN GEAR TRANSMISSION ed Nov. 30. 1926 2 Sheets-Sheet 2 ZP-eyen for en/ara/Zraren Patented Dec. 4, 1928.

UNHTE STATELS PATENT QFFECE.

LORENZ KONRAD BRAREN, OF MUNICI-I, GERM NY, ASFJGNOR T() FIRM: FRIEDRICH DECKEL, PRAZISIONSMECHANIK 'UND MASCHINENBAU, OF MUNICH, BAVARIA,

GEAR TRA.

'NSM'.SSION.

Application filed November 30, 1926, Serial Ne. 151,800, and in Germany December 5, 1925.

The invention relates to gear transmissions and has for its object to provide a tmnsmission with a iircfl speed ratio of a very simple. compact and durable form. This object is attained by arrancginre,l one or a plurality of intermediat(` discs between the fast and slowly rotating` members. This disc is mounted eccentrieallv en the fast member and is provided on the circumference with a number of teeth to engage with a set of holding' members, for instance rollers. The teeth on the circumference form a continuous cyeloidal curve or an equidistant to such a curve. The, term eyeloidal curve is meant to include troehoid, epicyeloid, epitrochoid. hynocycloid and bypotrochoid curves. The prolate tvpe of the curve is of special advantage for this purpose as it has no turning point and therefore a more favourable acceleration. The load with the prelato form of the curve furthermore not transmitted on a single line ef the dise during' a longer period as is the case with the normal curve.

Another object of my invention is to remove all banding strain from the fast as well as from the slow shaft Which object is attained by providingr a plurality of intermediate discs disposed angularlv to each other to compensate for the bending forces Another important object of my invention is to equalize the load ot' the transmitting pins which is attained by providingr a supportingr ring on the outside end of the pins and between the intermediate discs in case more than one are used. In case of Severely loaded transmissions the ringl may be supported radially.

I furthermore make according to my invention all pins of such a diameter that they deflect a. triiie under load equalizinal thus any possible inaccuracies in the form of the curve or in the location of the pins.

Another object of my invention is to provide transmitting pins of the same number as there are teeth in the intermediate disc in order to attain a very compact construction. VVben using a plurality of discs the number of teeth must be devisible by the number of dises in order to be able to locate the bores for the transmitting pins in the teeth.

The above and various other important improvements will be hereinafter fully described and claimed. In order that this my invention may be more readily understood reference is made to the accompanying sheets of drawings which show how the invention may be carried into practical eil'ect.

Fig'. 1 is a longitudinal section of a gear transmission with tivo intermediate plates.

Fig. 2 is a cross section of the transn'iission shown in Figure 1. l

Figi. 3 is a longitudinal section of a transmission With one intermediate plate.

Fig. 4- is a cross section of a transmission as shown in Figure 2 but with special holdmi,T means for the equalizing` ring.

Fig. 5 shows a differentarrangement of the transmitting` pins and a single set of holding members for two intermediate dises.

Fig. G shows the use of an epicvcloid for the teeth on the disc. L

Fia. 7 shows the disc with a prolate trochoid.

Referring te the Figures 1 and 2 the fast rotating` shaft 1 which for instance may be the shaft of an electromotor is fastened by a lrey 41 to a bushing' 4 which is journaletl in a bore of the cover 'i'. A crank shaft 4t2 fastened to the bushing' 4 by a number of key lile projections 43 has tivo cranks 2 and 3 disposed at 180 to each other. The crankshaft l2 is journaled in tire roller bearings 5 and (i of which the first is supported by the cover 7 While the latter is carri-ed by the slowly rotating shaft 8. Two intermediate discs 9 and 10 are mounted on roller bearings 11 and 12 to turn freely on the cranks 2 and 3.

The discs 9 and 10 are fashioned on the circumference with a number of teeth the exact shape of which will be described later. The teeth stand in engagement With rollers 13 and 14 turnably mounted on pins 15 and 16. The pins 15 are fastened in the cover 7 while an equal number of pins 16 are fastened in the housing 17. The number of rollers in engagement With each disc differs by one from the number of teeth. The shape of the curve and the direction of rotation is determined by this relation. An epicyeloid or epitrochoid is required When the number of the holding members 14 eX- eeeds the number of teeth by one. The crankshaft 12 and the slowly rotating shaft 8 in this case rotate in opposite directions. Then however the number of the holding members 14 is smaller by one than the number of teeth an hypoeycloid or hypotroehoid is required. Both shafts rotate in this case in ille saule dilertion. For translllittinggl the turning moment from tlle discs to the slowly rotating' slnll't or vire Versa there are lll-olillrd :l number ol' pins l?) Y[":lslened ill a Ilallglx ll oi' the slow sllalil` il'. llolcs 45 in identical number with the pins are bored ill ille discs. For heavy servire the nunlller oli llle holes l5 ill tlle discs should correspond to the number nl teeth as it illus becomes llosA sible to lorzlle tlle holes in ille teeth wherebyY the radius el' ille plus from tlle centerline is increased and llle load on the pins for respondingly decreased. there size is not o1 great inlllorlanre the dise may lle made larger in diameter and a dilerent number of holesl L15 be provided than there are teeth (see Figure 5). The rollers 13 and 14 in this case may be arranged on a single pin 15. To reduce the 'Friction of the pins in the holes` 45 rollers 20 and 2] are interposed. The diameter of the holes 45 is equal to tbe diameter of the rollers 2O plus twice the eccentricity of the cranks, The pins 19.y 15 and 1G are (jlinlel'lsioned to deflect ,slightly under the load so as to equalize any inaccuracies of lnallufacture.

In order to distribute ille load equally on all pills rings 18, 22 and 23 are provided. The ring 1S supports ille free ends of the pins 15 and 1G which latter are spaced halt a division apart in relation to each olller. The ring' 22 is arranged between the two dises 9 and 10 alld may be supported radially in a ball bearing- 46 for Very heavy seri'- ice. Another inode of supporting the rings 22 and is shown on Figure 4 Where two pins 24 and 25 a tlille smaller than the diameter of the rollers 20 carry the rings. Normally such a support is not necessary. T he ring 23 finally is located over the ends ol the pins 19, crosspins 47 holding the rings and tlle rollers 20 axially.

Counterweigllts 26 and 27 on the fast sleeve 4 and on the crankshaft 42 form a couple to compensate for tllecouple caused by the discs 9 and 10.

The slow Shaft 8 is supported radially and held axially by two roller bearings 48 and 49 in the housing; 17. The cover 7 is fastened by screws 50 tothe housing 17 forming' thus an oiland airtight container. Two openings 51 are provided of which one only is shown, the one for filling with lubri cant and the other for determining the oil level. The housing may be shaped to serve as end plate for an electromotor, the arma.- lnre shaft being supported by the cover 7.

l n.' i., smlisoarlmshown n ifrure 3 uses on int r7.9 f 1.. .i new es i light and medium serifii'cleggglor responding parts are designated with identical numbers as in the Flgures 1 and 2 increased by one hundred. The fast sleeve 104 is supported in a ball bearing 161 which is held in place in the cover 107 by an end plate IGZ. l`\ dasll ring' llll |lel l'rillionally on tll(l sleeve `l thrown ollia :lily lubricant passing; Illronlrll the roller Ilwll'ingl, :l paslill llernlillliuyj il lo return lo [he oil lllaulller. 'Vile eollnllllwlA "elite lll and lil are :lrranilfll on llolll sil.Vw ol' and :lose lo ille single inlellnellillte dil-e lll). 'lflle heul;- inu' lliT in turned down on the outside to 'lornl a sont 105 l'or i'zlslelliiln` ille complete gear lo :ln end plate ll'l ol. an elecllonlotor or to a suitable bracket.

In the Figures 5 and l ille shape ol two dillel'ent curves 'lor the in'erulediate dise are shown of which ille curve on llieul'e t3 is the equidisanl lo all epi-fzycloid 2.() and the curve on Figure 7 the equidislant to a prelato epitrochoid 231. The points 30 on tlle equidistant llave to carry the load during` a longer time than llle rest of the curve due lo the reversal ol the eur-xe 29 in the' points This disadvantage is entirely removed in a prelato troelloid where the distance c of the tracingl point l2 from tllc center is about equal to @all of the radins r ol tlle rolling circle as indicated by 34. The distance e of course lnust correspond exactly with the eecenlricity of the crank. .il method and means for producing such curves is described ill my copending :n ullicaiion, production o'lE cycloidal curves. Serial No. 151,799, filed Norelllbel 3U, 1926.

Haring new particularly desrrilled and ascertained the nature of my said invention I do not Wish lo be understood limitinglllyself t0 the exact details oil construction as obviously many modifications will occur to a person skilled in the art.

7What I claim is:

1. In a gear transmission a Vlast rotating member, a slowly rotating member, ll ec centric on rotating member, a `dise loxut-ed/to turn on said eccentric7 the circumference of said dise forming a eontinuous cyeloidal curve` members to engage with said cyeloidal curve, and means for connecting said disk and said slowly rotating member.

2. In a gear transmission a fast rotating' .nlenlberi a slowly rotating members an eccentric on said fast rotating lnelnbrrga disc mounted to turn o-n said eccentric, the eircumference of said dise forming` tbe equidistant to a continuons cycloidal curve, members to engage with said equidistant. and means for connecting said disk and said slow ly rotating member.

3. In a gear transmission a fast rotating; member, a slowly rotating member, an eccentric on said fast rotating member, a disc mounted to turn on said eccentric, the eircumferenee of said dise forming the equi distant to a continuous epitroclloidal curve, members in engagement with said equidistant, and means for connecting said disk and said slowly rotating member.

il. In a gear transmission a fast rotating member, a lslowly rotating member, an eccentric on said fast rotating member, a disc n'lounled rotatably on said. eccentric, the circumference of said disc forming the equilstanlto a continuous prolate epitrochoid ol' which the distance of the generating point Alroni the center of the rolling circle equals about 5)., ol" the radius of the rolling circle, members in engagement with said equidistant, and means for connecting said disk and said slowly rotating member.

5. In a gear transmission a fast rotating member, a slowly rotating member, two eccentric portions on said fast member, dis posed at 18()O to each other, two discs one on each eccentric portion for removing any bending strain from said fast rotating member, the circumference of said discs orn'iing a continuous cycloidal curve, members in engagement with said discs` and means for connecting said disk to said slowly rotating member.

6. In a gear transmission a fast rotating member, a slowly rotating member, a plurality of eccentric portions on said fast rotating member, a plurality of discs one on each eccentric portion, the circumference of each disc forming a continuous cycloidal curve, stationary members in engagement with said discs, and a plurality of dogs fast-cned in said slowly rotating member for transferring the load between said discs and said slowly rotating member.

7. In a gear transmission a fast rotating member, a slowly rotating member, a plurality of eccentric po-rtions on said fast rotating member, a plurality of discs, arranged rotatably one on each said eccentric portion, the circumference of each disc forming a continuous cycloidal curve, stationary mem bers in engagement with said discs, and a plurality of dogs fastened in said slowly rotating member for transmitting the load between said discs and said slowly rotating member, the number of teeth on each disc a multiple of the total number of discs employed and the number of dogs in identical number with the number of teeth on the discs.

8. In a gear transmission a fast rotating member, a slowly rotating member, an eccentric portion on said fast rotating member, a disc rotatable on said eccentric, the circumference formed with a continuous cycloidal curve, members in engagement with said cycloidal curve, and dogs in engagement with said disc said dogs dimensioncd to permit of slight deflections for equalizing any inaccuracies.

9. In a gear transmission a 'last rotatingl member, a slowly rotating member, an eccentric portion on said fast rotatingYnicniber, a disc rotatable on said eccentric', the cil cumfercnce an equidir-:tant to a continuous cycloidal curve, rolling members in engagement with said curve, and pins for said rolling members` of such size as to permit of slight dcfiections for ci'lualizing any inac euraeies.

10. In a gear transmission a fast rotating member, a slowly rotating member, an eccentric portion on said fast rotating member, a disc rotatable on said eccentricrwith the circumference a continuous cyeloidal curve, stationary members in engagement with said cycloidal curve, a plurality of dogs fastened in said slowly rotating member, said dogs transmitting the turning moment between said slowly rotating shaft and said dise, and a supporting ring for said dogs.

ll. In a gear transmission a fast rotatingl member, a slowly rotating nieinber, a plurality of eccentrica on said fast rotating member, a plurality of discs rotatable one each on said eccentrica, the circumference of said discs forming a continuous eycloidal curve, stationary members in engagement with said cycloidal curves, a plurality o'l dogs transmitting the turning moment between said slowly rotating shaft and said discs, and a plurality of rings for supporting said dogs.

12. In a gear transmission, the combination with a driving member, of a trans mission member rotatably and eccentp'C/ally mounted on said driving member, sai transmission member having a toothed portion, a plurality of pockets in said transmission member, each of said pockets extending partially into one of the teeth of said toothed portion, a plurality oi members rotatable relative to each other and to said driving member, means on one of said plurality of members for engaging the toothed portion of said transmission member, and means on another of said plurality of meme bers Jfor engaging the pockets in said transmission member'.

In testimony whereof I hereunto alix my signature.

LORENZ KONRAD BRAREN. 

